Web-slack preventer for multicolor perfecting printing presses



Jan. 11,1927. 1,614,178

H. M. BARBER WEB SLACK PREVENTER FOR MULTICOLOR PERFECTING PRINTING PRESSES Filed April 19. 1926 INVENTOR ATTORNEYS Patented J an. 11, 192?.

UNITED STATES PATENT OFFICE.

HOWARD M. BARBER, OF PAWCATUCK, CONNECTICUT, ASSIGNOR TO C. B. COTTRELL & SONS COMPANY, OF WESTERLY, RHODE ISLAND, A CORPORATION OF DELAWARE.

WEB-SLACK PREVENTER FOR MULTICOLOR PERFECTING PRINTING PRESSES.

Application filed April 19, 1926. Serial No. 103,024.

In multi-color web perfecting printing presses where the plate and impression cylinders of the first printing unit are the same diameters as the plate cylinders of the second printing unit, and the impression cylinder of the second printing unit is twice or any other multiple of the diameter of the impression cylinder of the first printing unit, it has been very difiicult to so feed the Web to the second printing unit as to prevent slack in the web.

To cause the first printing unit to run in unison with the second printing unit so that the web will be fed properly to the second printing unit, to prevent slack in the web, I have found that it is necessary to make the bearer diameters of the plate and impression cylinders of the first printing unit a predetermined amount less than their aliquot part of the bearer diameter of the impression cylinder of the second printing unit.

F or example: In a machine where the impression cylinder of the first printing unit is approximately one-half the diameter of the impression cylinder of the second printing unit, the bearer diameters of the impression and plate cylinders of the first printing unit must be made slightly smaller than one-half of the bearer diameter of the impression cylinder of the second printing unit to eliminate any tendency to produce slack in the web between the two printing units.

A practical embodiment of my invention is represented in the accompanying drawing which discloses in diagram a multi-color web perfecting printing press arranged toprint two colors upon the first side of the Web and then four colors upon the other side of the web.

The two plate cylinders ofthe first printing unit are denoted by 1, 2 and their common impression cylinder by 3. he four plate cylinders of the second printing unit are denoted by 4, 5, 6, 7 and their common impression cylinder by 8.

The impression cylinder 8 of the second printing unit is shown as being twice the diameter of the impression cylinder 3 of The web which is the first printing unit. led in the usual manner through the first and second printing units is denoted by E). In this case the bearer diameters of the plate and impression cylinders 1, 2 and 3 of the first printing unit should be slightly less than one-halt the bearer diameter of the impression cylinder 8 of the second printing unit, to prevent slack in the web.

vVhat I claim is 1. In a multi-color web perfecting printing press, two printing units in which the diameter of the impression cylinder of the first printing unit is an aliquot part of the diameter of the impression cylinder of the second printing unit, the bearer diameters of the plate and impression cylinders of the first printing unit being a predetermined amount less than their aliquot part of the bearer diameter of the impression cylinder oi the second printing unit, whereby the first impression unit is caused to run in unison with the second printing unit to prevent web slack between the printing units.

2. In a multi-color web perfecting printing press, two printing units in which r diameter of theimpression cylinder of the first printing unit is one-halt the diameter of the impression cylinder otl-the second printing unit. the bearer diameters of the plate and impression cvlinders of the first printing unit being a predetermined amount less than one-half the bearer diameter of the impression cylinder of the second printing unit, whereby the first printing unit is caused to run in unison with the second printing unit to prevent web slack between the printing units.

In testimony, that I claim the foregoin as my invention, I have signed my name this 29th day of March A. D. 1926.

HOWARD M. BARBER. 

